Developing column material for the separation of serum amyloid P and C reactive protein from biological sources

Specific DNA aptamer-immobilized cryogel membranes as novel bioaffinity supports and their potential for the purification of activated protein C

Activated protein C (APC), a serine protease produced from zymogen protein C (PC), is the key enzyme of the protein C pathway. APC has anticoagulant, anti-inflammatory, and cytoprotective features. APC has recently been shown to significantly reduce coagulation as well as mortality in patients with severe sepsis. Herein, we aimed to develop an affinity support material that allows the purification of plasma APC for the first time. In this research, a novel APC-specific DNA aptamer-based poly(2-hydroxyethyl methacrylate-glycidyl methacrylate) (poly(HEMA-GMA/DNA-Apt)) macroporous cryogel membrane at different molar ratios was prepared using affinity binding method and their potential for purification and identification of APC was investigated. The DNA aptamer-immobilized cryogels were characterized to examine their structural and morphological properties. The effect of pH, initial concentration, temperature, ionic strength difference, and flow rate changes was examined. Selectivity studies were performed in the presence of APC and competitive proteins, and cryogel support materials were shown to have a very high affinity for APC. Adsorption capacity was found to be 89.02 mg/g. Finally, NaCl revealed efficiency for APC desorption and the reuse of cryogels was successfully tested for ten cycles.

Concanavalin A photocross-linked affinity cryogels for the purification of horseradish peroxidase

The present study describes an easy and efficient procedure for the purification of horseradish peroxidase from horseradish roots. For this purpose, supermacroporous cryogels having Concanavalin A were prepared by photosensitive cross-linking polymerization. Horseradish peroxidase binding and elution from the prepared cryogels were carried out changing various parameters such as initial peroxidase concentration and pH. The best binding performance was obtained at pH 7.0. The maximum horseradish peroxidase binding of the cryogels was found to be 3.85 mg g−1 cryogel. Horseradish peroxidase purification from crude extract resulted in 115.1-fold. SDS-PAGE analysis and circular dichroism measurements indicated that the horseradish peroxidase purification from horseradish roots was successfully carried out.

Multiple gene and transcript variants encoding trout C-polysaccharide binding proteins are differentially but strongly induced after infection with Aeromonas salmonicida

Two 'trout C-polysaccharide-binding proteins,' TCBP1 and -2, with relevance to early inflammatory events have been discovered in the last century. The present study characterises the respective cDNA sequences from rainbow trout (Oncorhynchus mykiss), including multiple TCBP1 transcript variants. These variants are generated either by the use of alternative splice sites or the exclusion of exons. The longest mRNA isoform, TCBP1-1, encodes a 245-aa protein with a large signal peptide and a complement component C1q domain. The shortest mRNA isoform, TCBP1-5, contains a premature termination codon and hence fails to encode a functional factor. The 224-aa-long TCBP2 protein consists of a comparably shorter signal peptide and a pentraxin domain. Evolutionary analyses clearly separated TCBP1 and -2 because of distinctive protein motifs. Expression profiling in the liver, spleen, and head kidney tissues of healthy trout revealed that TCBP2 mRNA concentrations were higher than the concentrations of all five TCBP1 mRNA isoforms together. The hepatic levels of these TCBP1 variants increased significantly upon infection with Aeromonas salmonicida, whereas TCBP2 transcript levels rose moderately. As the biological function of TCBP1 is barely understood, we tagged this factor with the green fluorescent protein and visualised its expression in HEK-293 cells. Overexpression of TCBP1 increased the level of active NF-κB factors and induced cell death, indicating its involvement in proapoptotic NF-κB-dependent signalling routes.